/*
 * MIT License
 *
 * Copyright (c) 2018 Hippolyte Barraud
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#pragma once

#include <cstdint>

namespace ultramarine::impl {
    // Based on code from Python's crcmod module. Polynomial "crc-32".
    // polynomial: 0x104C11DB7, bit reverse algorithm:
    //  crcmod.Crc(0x104C11DB7, initCrc=0, xorOut=0xFFFFFFFF)
    static constexpr const uint32_t table[256] = {
            0x00000000U, 0x77073096U, 0xEE0E612CU, 0x990951BAU, 0x076DC419U,
            0x706AF48FU, 0xE963A535U, 0x9E6495A3U, 0x0EDB8832U, 0x79DCB8A4U,
            0xE0D5E91EU, 0x97D2D988U, 0x09B64C2BU, 0x7EB17CBDU, 0xE7B82D07U,
            0x90BF1D91U, 0x1DB71064U, 0x6AB020F2U, 0xF3B97148U, 0x84BE41DEU,
            0x1ADAD47DU, 0x6DDDE4EBU, 0xF4D4B551U, 0x83D385C7U, 0x136C9856U,
            0x646BA8C0U, 0xFD62F97AU, 0x8A65C9ECU, 0x14015C4FU, 0x63066CD9U,
            0xFA0F3D63U, 0x8D080DF5U, 0x3B6E20C8U, 0x4C69105EU, 0xD56041E4U,
            0xA2677172U, 0x3C03E4D1U, 0x4B04D447U, 0xD20D85FDU, 0xA50AB56BU,
            0x35B5A8FAU, 0x42B2986CU, 0xDBBBC9D6U, 0xACBCF940U, 0x32D86CE3U,
            0x45DF5C75U, 0xDCD60DCFU, 0xABD13D59U, 0x26D930ACU, 0x51DE003AU,
            0xC8D75180U, 0xBFD06116U, 0x21B4F4B5U, 0x56B3C423U, 0xCFBA9599U,
            0xB8BDA50FU, 0x2802B89EU, 0x5F058808U, 0xC60CD9B2U, 0xB10BE924U,
            0x2F6F7C87U, 0x58684C11U, 0xC1611DABU, 0xB6662D3DU, 0x76DC4190U,
            0x01DB7106U, 0x98D220BCU, 0xEFD5102AU, 0x71B18589U, 0x06B6B51FU,
            0x9FBFE4A5U, 0xE8B8D433U, 0x7807C9A2U, 0x0F00F934U, 0x9609A88EU,
            0xE10E9818U, 0x7F6A0DBBU, 0x086D3D2DU, 0x91646C97U, 0xE6635C01U,
            0x6B6B51F4U, 0x1C6C6162U, 0x856530D8U, 0xF262004EU, 0x6C0695EDU,
            0x1B01A57BU, 0x8208F4C1U, 0xF50FC457U, 0x65B0D9C6U, 0x12B7E950U,
            0x8BBEB8EAU, 0xFCB9887CU, 0x62DD1DDFU, 0x15DA2D49U, 0x8CD37CF3U,
            0xFBD44C65U, 0x4DB26158U, 0x3AB551CEU, 0xA3BC0074U, 0xD4BB30E2U,
            0x4ADFA541U, 0x3DD895D7U, 0xA4D1C46DU, 0xD3D6F4FBU, 0x4369E96AU,
            0x346ED9FCU, 0xAD678846U, 0xDA60B8D0U, 0x44042D73U, 0x33031DE5U,
            0xAA0A4C5FU, 0xDD0D7CC9U, 0x5005713CU, 0x270241AAU, 0xBE0B1010U,
            0xC90C2086U, 0x5768B525U, 0x206F85B3U, 0xB966D409U, 0xCE61E49FU,
            0x5EDEF90EU, 0x29D9C998U, 0xB0D09822U, 0xC7D7A8B4U, 0x59B33D17U,
            0x2EB40D81U, 0xB7BD5C3BU, 0xC0BA6CADU, 0xEDB88320U, 0x9ABFB3B6U,
            0x03B6E20CU, 0x74B1D29AU, 0xEAD54739U, 0x9DD277AFU, 0x04DB2615U,
            0x73DC1683U, 0xE3630B12U, 0x94643B84U, 0x0D6D6A3EU, 0x7A6A5AA8U,
            0xE40ECF0BU, 0x9309FF9DU, 0x0A00AE27U, 0x7D079EB1U, 0xF00F9344U,
            0x8708A3D2U, 0x1E01F268U, 0x6906C2FEU, 0xF762575DU, 0x806567CBU,
            0x196C3671U, 0x6E6B06E7U, 0xFED41B76U, 0x89D32BE0U, 0x10DA7A5AU,
            0x67DD4ACCU, 0xF9B9DF6FU, 0x8EBEEFF9U, 0x17B7BE43U, 0x60B08ED5U,
            0xD6D6A3E8U, 0xA1D1937EU, 0x38D8C2C4U, 0x4FDFF252U, 0xD1BB67F1U,
            0xA6BC5767U, 0x3FB506DDU, 0x48B2364BU, 0xD80D2BDAU, 0xAF0A1B4CU,
            0x36034AF6U, 0x41047A60U, 0xDF60EFC3U, 0xA867DF55U, 0x316E8EEFU,
            0x4669BE79U, 0xCB61B38CU, 0xBC66831AU, 0x256FD2A0U, 0x5268E236U,
            0xCC0C7795U, 0xBB0B4703U, 0x220216B9U, 0x5505262FU, 0xC5BA3BBEU,
            0xB2BD0B28U, 0x2BB45A92U, 0x5CB36A04U, 0xC2D7FFA7U, 0xB5D0CF31U,
            0x2CD99E8BU, 0x5BDEAE1DU, 0x9B64C2B0U, 0xEC63F226U, 0x756AA39CU,
            0x026D930AU, 0x9C0906A9U, 0xEB0E363FU, 0x72076785U, 0x05005713U,
            0x95BF4A82U, 0xE2B87A14U, 0x7BB12BAEU, 0x0CB61B38U, 0x92D28E9BU,
            0xE5D5BE0DU, 0x7CDCEFB7U, 0x0BDBDF21U, 0x86D3D2D4U, 0xF1D4E242U,
            0x68DDB3F8U, 0x1FDA836EU, 0x81BE16CDU, 0xF6B9265BU, 0x6FB077E1U,
            0x18B74777U, 0x88085AE6U, 0xFF0F6A70U, 0x66063BCAU, 0x11010B5CU,
            0x8F659EFFU, 0xF862AE69U, 0x616BFFD3U, 0x166CCF45U, 0xA00AE278U,
            0xD70DD2EEU, 0x4E048354U, 0x3903B3C2U, 0xA7672661U, 0xD06016F7U,
            0x4969474DU, 0x3E6E77DBU, 0xAED16A4AU, 0xD9D65ADCU, 0x40DF0B66U,
            0x37D83BF0U, 0xA9BCAE53U, 0xDEBB9EC5U, 0x47B2CF7FU, 0x30B5FFE9U,
            0xBDBDF21CU, 0xCABAC28AU, 0x53B39330U, 0x24B4A3A6U, 0xBAD03605U,
            0xCDD70693U, 0x54DE5729U, 0x23D967BFU, 0xB3667A2EU, 0xC4614AB8U,
            0x5D681B02U, 0x2A6F2B94U, 0xB40BBE37U, 0xC30C8EA1U, 0x5A05DF1BU,
            0x2D02EF8DU
    };

    static constexpr uint32_t crc32(const char *data, uint32_t len, uint32_t crc = 0) {
        crc = crc ^ 0xFFFFFFFFU;
        for (uint32_t i = 0; i < len; i++) {
            crc = table[(uint8_t)*data ^ (crc & 0xFFU)] ^ (crc >> 8U);
            data++;
        }
        crc ^= 0xFFFFFFFFU;
        return crc &= ~(1U << 0U); // clearing the least-significant bit
    }
}